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Abstract: V magistrskem delu smo testirali vpliv cemprinovega lesa na rast gliv in oblikovanje spor Aspergillus niger ter Penicillium roqueforte. Vpliv lesa smo testirali tako, da smo glive inkubirali v škatlah iz cemprinovega lesa. Kot primerjalno kontrolo za analizo rasti gliv smo uporabili še škatle iz bukovega in smrekovega lesa, plastike in čisto eterično olje cemprina. Največji zaviralni učinek na rast testiranih gliv smo opazili v škatlah iz cemprinovega lesa, sledile so plastične škatle z dodatkom eteričnega olja cemprina. Rast gliv v drugih škatlah je bila primerljiva. Cemprinov les je imel največji zaviralni učinek na rast glive P. roqueforte, hkrati pa je zavrl tudi oblikovanje spor gliv. Cemprinov les ima zaradi svojih protiglivnih lastnosti potencial za uporabo v živilski industriji kot material za izdelavo škatel za shranjevanje kruha in končnih pekovskih izdelkov, kjer sta pojav in kvar zaradi plesni pogosta.
Keywords: Pinus cembra, cemprin, Penicillium roqueforte, Aapergillus niger, protiglivno delovanje
Published in DKUM: 03.09.2024; Views: 47; Downloads: 7
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Abstract: As a result of worried consumer pressure, European supermarket chains (ESC) have developed very strict rules about the number and concentration of pesticide active substance residues (AS) accepted in fruits. So-called fruit quality toxicological burden indicators were developed. If fruit suppliers do not comply with ESC requirements, their fruit is often rejected. It is becoming increasingly difficult for apple producers to meet all the requirements of the ESC, so they need new residue reduction tools. One of the options to lower the concentrations of residue on apples is a preharvest application of low-risk preparations (LRP) based on potassium bicarbonate (KHCO3) = PBC, coconut di-ethanol amide ((CH3(CH2)nC(=O)N(CH2CH2OH)2) = DEA, hydrogen peroxide (H2O2) = HP, and a mixture of microbes (EM) that have the ability to dissolve or disintegrate the AS residue. Trials were carried out to test the concept mentioned above. The application of LRP during the last four weeks of preharvest significantly reduced the residue concentration of pesticide AS in apples. Reduction rates among 25 active substances ranged from 0 to 100%, depending on the combination of LRP and AS. HP had the highest capacity to accelerate AS degradation, PB was the second most efficient, and DEA and EM displayed a low residue disintegration ability. The application of the tested LRP can enable apple growers to produce fruits with significantly lower residue concentrations and allows them to comply more successfully with strict ESC rules based on the calculations of toxicological burden indicators.
Keywords: hydrogen peroxide, potassium bicarbonate, effective microbes, detergent, pesticide residues, fruit marketing rules
Published in DKUM: 19.04.2024; Views: 253; Downloads: 3
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Abstract: The long-term use of copper (Cu) fungicides in viticulture in Europe has led to Cu accumulation in vineyard top soils. However, less is known about the accumulation of Cu in grapevine grafts after the callusing process/before planting in the nursery. This paper presents the capacity of 5BB and SO4 rootstocks to accumulate Cu, as well as the patterns of translocation in the grafts. After heat forcing (callusing), the grapevine grafts of Sauvignon Blanc on 5BB and SO4 rootstocks were grown in pots for six months in a glasshouse and exposed to various Cu formulations (Cu-oxychloride, Cu-gluconate) and concentrations in peat (50, 150, 500, and 1000 mg Cu of dry weight (DW)). In addition to monitoring the shoot growth dynamics and analyzing the copper content in graft organs, bioaccumulation (BAFs) and translocation factors (TFs) of Cu were calculated. The mean Cu concentrations were ranked as follows: roots (15–164) > rootstock trunks (8–38) > canes (5–21) mg kg−1 DW. The Cu concentrations depended on the Cu formulation and concentration in the substrate. Higher Cu content was found in the roots of both rootstocks (5BB and SO4, 23–155 and 15–164 mg kg−1 DW, respectively) and the lowest in the canes (less than 10 mg kg−1 DW) of grafts grown in Cu-oxychloride-treated peat. Based on the BAFs and TFs, both rootstocks could be considered as Cu exclusive. A higher translocation rate was determined in systemic Cu-gluconate and SO4 rootstock. With shoot length measurements, the significant inhibitory effects of Cu on grapevine grafts growth could not be confirmed, despite the inhibitory effects that were clearly expressed in the first two months of growth. Soils containing more than 500 mg Cu/kg−1 are less suitable for growing vine grafts.
Keywords: grapevine grafts, copper accumulation, Cu-oxychloride, Cu-gluconate, 5BB and SO4 rootstocks
Published in DKUM: 08.12.2023; Views: 457; Downloads: 19
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Abstract: V letu 2021 smo izvedli poljska poskusa, v katerih smo preučevali učinkovitost ekološkega in integriranega škropilnega programa na zatiranje stenice marmorirane smrdljivke (Halyomorpha halys Stål) v dveh ločenih nasadih jablan na Primorskem. Ocenjevali smo velikost populacije odrasle stenice, njenih ličink in delež plodov s poškodbami v 9- do 12-dnevnih presledkih. Škropilni program v ekološkem nasadu, temelječ na rastlinskih izvlečkih, naravnih piretrinih, spinosadu, kaolinu, naravnih milih in azadirahtinu, je bil v povprečju med 45- in 66-odstotno učinkovit za zatiranje stenic in je za 65 do 78 odstotkov zmanjšal delež plodov s poškodbami ob obiranju. Pri dveh integriranih škropilnih programih, temelječih na uporabi snovi acetamiprid, deltametrin, fosmet, spinosad in rastlinskih izvlečkov, smo dosegli od 69- do 93-odstotno učinkovitost pri zatiranju odraslih stenic. Uporaba pripravkov v integriranem programu je za 70 do 80 odstotkov zmanjšala delež plodov, poškodovanih od stenic, ob obiranju. Iz podatkov, ki smo jih dobili v poskusu, lahko sklepamo, da so lahko škropilni programi, ki temeljijo na podlagi testiranih razpoložljivih aktivnih snovi, do 80-odstotno učinkoviti. To kaže, da zgolj z uporabo testiranih pripravkov ni možno zagotoviti dovolj temeljitega zatiranja stenice. Hkrati je z uporabo insekticidov treba izvajati še druge biotične in biotehniške metode zatiranja.
Keywords: marmorirana smrdljivka, kemično zatiranje, jablana
Published in DKUM: 04.07.2023; Views: 744; Downloads: 49
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Abstract: V sezoni 2018 smo v nasadih jablan sort Gala, Fuji in Zlati delišes testirali 0-residue koncept varstva pred škodljivimi organizmi. Standardni intenzivni integriran škropilni program (V1) smo primerjali z dvema 0-residue škropilnima programoma V2 in V3. V programih V2 in V3 smo v drugem delu sezone, od začetka julija naprej, namesto kemičnih FFS uporabljali alternativne pripravke, ki jih uporabljamo v ekološki pridelavi. Izvajanje V2 in V3 škropilnega programa je zagotovilo skoraj enako učinkovito zatiranje bolezni in škodljivcev kot škropilni program V1. Zaradi izvajanja V2 in V3 škropilnih programov ni prišlo do značilnega znižanja pridelka in do značilnega znižanja deleža jabolk prvega razreda. Pri V2 in V3 smo značilno znižali število najdenih aktivnih snovi s koncentracijo nad 0,01 mg/kg in tudi parametra kumulativni % MRL in % ARFD, ki sta v trgovskih verigah zelo pomembna pri presoji sprejemljivosti jabolk za odkup. Pri programih V2 in V3 smo lahko dosegli zahtevana merila trgovskih verig.
Keywords: 0-residue, Gala, Fuji, Zlati delišes, integrirana pridelava
Published in DKUM: 03.05.2023; Views: 516; Downloads: 38
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